Book marker



FIG. 1 is a perspective view of a book marker;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a top plan view of the book marker; and,

FIG. 7 is a bottom plan view thereof.

The ornamental design for a book marker, as shown and described.